Home nurses and home care workers share the care for a person with dementia with family caregivers, and are confronted with their needs for medical and service-related information, for advice on how to cope with the behaviour changes, and for emotional support. The first objective of the present study was to describe some of the conditions for effective counselling, such as the perception that knowing the diagnosis has positive consequences for the formal caregivers. A second objective was to describe the formal caregivers’ counselling practice, and ascertain its relationship with the psychological variables of attitudes, self-efficacy and subjective norm. A postal questionnaire was sent to 287 home nurses and 1259 home care workers in a defined region of Belgium; the questionnaire was returned by 169 home nurses (58.9% response) and 665 home care workers (52.8% response). The Theory of Planned Behaviour was the organising framework which underpinned the development of the instruments. Only the 168 home nurses and 601 home care workers reporting experience with caregiving to people with dementia were included in the analysis. Formal caregivers indicated that knowing the diagnosis was important, but it could facilitate or hinder caregiving. They were able to describe behavioural characteristics which are indicative of dementia, but only in a limited way, and their strategies to uncover the diagnosis were also limited. Formal caregivers reported that they supported family members emotionally, advised about communication with the person with dementia and informed family caregivers about services. However, providing family caregivers with information about dementia lagged behind these forms of support. In general, nurses scored higher than home care workers. Multiple linear regression analysis was used to investigate the relationships between self-reported practice and the concepts of the model. In both professions, attitudes and self-efficacy were found to be strong independent predictors, and the implications for practice are discussed.